Allen has led the auditing and consulting services firm through a tumultuous time in the industry, marked by corporate scandals and stricter regulation of accounting practices under the Sarbanes-Oxley Act. When she was elected board chair in May 2003, Allen became the highest-ranking woman in Deloitte's history. Prior to that, she was a managing partner and board member. She has spent her entire career at the firm, starting in the Boise office in her home state of Idaho. In October 2005, President George W. Bush appointed Allen to serve on the President's Export Council, which advises on international trade. She also serves on the boards of the Los Angeles Area Chamber of Commerce, United Way of Greater Los Angeles, and the YMCA of Metropolitan Los Angeles. Claire Miller

Published sources include the women's official biographies, Factiva, International Who's Who of 2005, Marquis Who's Who, World Almanac of Famous People, Palgrave Who's Who 2005, the Congressional Yellow Book, the Judicial Yellow Book, Europa World Year Book, Hoover's Online, U.S. Securities and Exchange Commission filings, World Economic Forum, the World Book Encyclopedia. Rankings generated by combining various financial figures with other media and biography metrics; global media mentions from Factiva.